Ok, sorry for not giving you much info. Its my partners computer, about 4 years old and using windows xp. Its running very slow, keeps freezing etc and at times sounds like it want to take off! Tried all the usual system tools etc, disk cleaning to no avail. She has in the past been obsessed with downloading any free pop up advert known to man and I suspect there is just so much rubbish on the drive. I've done an up to date virus check and used spyware programs as well to help clean it up. I followed the instruction book advise to create a recovery disk, but needless to say the computer wouldn't allow it because one had already been made. Equally predicatably my better half cannot locate said recovery disc. Thanks for the advise so far tho.

c) Clean the registry -- Free Registry cleaners :- RegscrubVistaXp click hereRegseeker click hereTweakNow RegCleaner 1.3.2 click hereEasycleaner click here ( Use with care, It advises you to back up the registry first, this is a good idea as it cleans rather aggressively. )

d) Pagefile (Virtual Memory) -- Rght click MY Computer - select propeties - Advanced tab - Performance - advanced tab - Virtual memory click change, you can put the page file on a differnt drive (if you have one), click custom size and set Initial size to one and a half times the amount of memory you have fitted i.e. 512MB memory = set to 768MB, set maximum to double your memory amount i.e. 512MB memory = 1024MB click ok.If your hard drive is full and there is not enough room for the pagefile this can slow down, freeze or even cause the PC to crash (restart).

ii) If you are using Windows XP or Vista, it's a good idea to convert your system drive to the NTFS file system if you have not already. In addition to providing numerous security and data recovery improvements over FAT32 (the file system of choice for Windows 9x/ME and XP Home) it can also speed up your system slightly.

In fact, the only real reason for sticking with the FAT32 file system for any of your data is if you have more than one operating system on your PC and the other OS's can only see FAT32 partitions (as would be the case with Windows 98, for example, which is incapable of reading NTFS data).

To convert your drives to NTFS:Right click on 'my computer' and select 'manage'From the computer management window, expand storage and select 'disk management.'Using the 'file system' column of the upper pane of this window, you can easily check what file system each of your logical drives is using. Make a note of this information.Now open a command prompt window by going to 'start\run' and typing 'cmd'To convert a disk to NTFS, type 'convert (drive letter): /fs:ntfs'So for example, if you were going to convert your C: drive, you would type 'Convert c: /fs:ntfs' at the prompt.

b) DiversObtain the newest drivers for your hardwareThis may seem a bit obvious, but keeping your system's drivers up to date can give both your performance and stability a boost. Video card manufacturers release updates especially often, and these can often give "significant boosts" to gaming performance as video card in question is "optimized."

Don't neglect the other components of your system either. Your motherboard manufacturer may have released newer versions of its Input/output drivers for your board, and sound cards and other peripherals can also benefit from newer software.

c) MemoryAdd more physical memory, this of course means opening the "box" and fitting a memory module, make sure you buy one that is suitable for your PC. Crucial .com click here will guide you through the process of slecting the correct memory. click here for a guide to fitting memory.